Identification and Functional Characterization of Brainstem Cannabinoid CB 2 Receptors
Marja D. Van Sickle, Marnie Duncan, Philip J. Kingsley, Abdeslam Mouihate, Paolo Urbani, Ken Mackie, Nephi Stella, Alexandros Makriyannis, Daniele Piomelli, Joseph S. Davison, Lawrence J. Marnett, Vincenzo Di Marzo, Quentin J. Pittman, Kamala D. Patel, Keith A. Sharkey- Multidisciplinary
The presence and function of CB 2 receptors in central nervous system (CNS) neurons are controversial. We report the expression of CB 2 receptor messenger RNA and protein localization on brainstem neurons. These functional CB 2 receptors in the brainstem were activated by a CB 2 receptor agonist, 2-arachidonoylglycerol, and by elevated endogenous levels of endocannabinoids, which also act at CB 1 receptors. CB 2 receptors represent an alternative site of action of endocannabinoids that opens the possibility of nonpsychotropic therapeutic interventions using enhanced endocannabinoid levels in localized brain areas.